lovecoding
/
VIP28


			
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							<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <style>
    #div1 {
      width: 200px;
      height: 200px;
      background: red;
    }

    #div2 {
      width: 200px;
      height: 200px;
      background: green;
    }

    .xx {
      background: #818181;
    }
  </style>
</head>

<body>
  <div id="div1">123</div>
  <div id="div2">222</div>

  <div class="xx">333</div>
  <div>444</div>
  <div class="xx">555</div>
  <div>666</div>

  <ul>
    <li class="xx">1</li>
    <li>2</li>
    <li class="xx">3</li>
    <li>4</li>
    <li class="xx">5</li>
    <li>6</li>
  </ul>
  <ul id="ul2">
    <li>1</li>
    <li class="xx">2</li>
    <li>3</li>
    <li class="xx">4</li>
    <li>5</li>
    <li class="xx">6</li>
  </ul>

  <button id="btn">点击</button>
  <button id="btn1">click</button>
  <script>
    var div1 = document.getElementById('div1')
    var div2 = document.getElementById('div2')
    var xx = document.getElementsByClassName('xx')//返回的是一个数组
    var btn = document.getElementById('btn')
    var ul1 = document.getElementsByTagName('ul')//返回的是一个数组
    var ul2 = document.getElementById('ul2')
    var li = ul2.getElementsByClassName('xx')
    var btn1 = document.getElementById('btn1')
    btn.onclick = function () {
      div1.style.background = 'orange'
      for (var i = 0; i < xx.length; i++) {
        xx[i].style.background = 'green'
      }
    }
    console.log(ul1)

    btn1.onclick = function () {
      for (var i = 0; i < li.length; i++) {
        li[i].style.background = 'orange'
      }
    }


  </script>
</body>

</html>